A simple compass can be made by placing a small bar magnet on a cork floating in water. Required:
a. What fraction of a plain cork will be submerged when floating in water?
b. If the cork has a mass of 11.5 g and a 22.5-g magnet, made of iron with a density 7.80 g/cm^3, is placed on it, what fraction of the cork will be submerged?
c. Will the bar magnet and cork float in ethyl alcohol?

22. the top of a cliff is located a distance h above the ground. at a distance h/2 there is a branch that juts out from the side of the cliff, and on this branch a bird's nest is located. two children throw stones at the nest with the same initial speed, one stone straight downward from the top of the cliff and the other stone straight upward from the ground. in the absence of air resistance, which stone hits the nest in the least amount of time?